Cognitive Results of CANTAB Tests and Their Change Due to the First Dose of Donepezil May Predict Treatment Efficacy in Alzheimer Disease

Impaired Executive Functioning Associated with Alcohol-Related Neurocognitive Disorder including Korsakoff's Syndrome

(1) Background: chronic alcohol use is consistently associated with impaired executive functioning, but its profile across the spectrum from mild to major alcohol-related cognitive impairment is, to date, unclear. This study aims to compare executive performances of patients with alcohol-induced neurocognitive disorder, including Korsakoff's syndrome (KS), by using a computerized assessment battery allowing a fine-grained and precise neuropsychological assessment; (2) Methods: performances of 22 patients with alcohol-related cognitive impairment (ARCI) and 20 patients with KS were compared to those of 22 matched non-alcoholic controls. All participants were diagnosed in accordance with DSM-5-TR criteria and were at least six weeks abstinent from alcohol prior to assessment. Executive function was evaluated using four subtests of Cambridge Neuropsychological Test Automated Battery (CANTAB®); (3) Results: significant differences between groups were found on spatial working memory (updating), sustained attention and inhibitory control, set shifting, and planning. Healthy controls performed significantly better than both patient groups (Games-Howell post hoc; p < 0.05), but no differences in performance were found between the ARCI and KS group; (4) Conclusions: ARCI and KS patients showed significant executive impairments, most prominent in updating, set-shifting and general planning abilities. Findings suggest equivalent levels of executive function in ARCI and KS patients. Our results highlight executive function as a significant hallmark of alcohol-induced neurocognitive disorder and stipulate the importance of early assessment and evaluation of skills to guide treatment.

Six-month intervention with wild blueberries improved speed of processing in mild cognitive decline: a double-blind, placebo-controlled, randomized clinical trial

BACKGROUND

As the sector of the population over 65y increases, cognitive decline and dementia become a public health issue. Interventions to improve brain health and thus, quality of life for older adults are needed.

OBJECTIVE

It was hypothesized that those consuming a flavonoid-rich, lyophilized wild blueberry powder would evidence improvements in cognitive performance as measured behaviorally and electrophysiologically compared to those consuming a placebo powder across a 6-month intervention period.

DESIGN

In a double-blind, randomized placebo-controlled trial, participants experiencing cognitive issues as determined by scores on the Montreal Cognitive Assessment (MoCA) were randomized to consume either wild blueberry (n  =  44) or placebo (n  =  42) powder daily for 6 months. Participants who were not experiencing any cognitive issues were included as a reference group (n = 45). Participants were tested at baseline and outcome on the Cambridge Neurological Test Automated Battery (CANTAB) and in an electrophysiological paradigm known as event-related potentials (ERP).

RESULTS

Tests of specific cognitive abilities using the CANTAB showed speed of processing not only improved in the blueberry intervention group relative to the placebo group across the 6-month intervention, but blueberries also restored speed of processing to the level of the reference group. The ERP results also showed that, relative to those consuming placebo, speed of processing improved for those in the blueberry group; this improvement was most prominent in those 75-80y.

CONCLUSIONS

Consumption of wild blueberries for six months improves cognitive aging sequelae by improving the speed of information processing in older adults.Trial registration: ClinicalTrials.gov identifier: NCT01515098.

Acute response to cholinergic challenge predicts long-term response to galantamine treatment in patients with Alzheimer's Disease

BACKGROUND

Cholinesterase inhibitors (CEIs) have been shown to improve cognitive functioning in Alzheimer's Disease (AD) patients, but are associated with multiple side effects and only 20-40% of the patients clinically improve. In this study, we aimed to investigate the acute pharmacodynamic (PD) effects of a single dose administration of galantamine on CNS functioning in mild to moderate AD patients and its potential to predict long-term treatment response.

METHODS

This study consisted of a challenge and treatment phase. In the challenge phase, a single dose of 16 mg galantamine was administered to 50 mild to moderate AD patients in a double-blind, placebo-controlled cross-over fashion. Acute PD effects were monitored up to 5 hours after administration with use of the NeuroCart CNS test battery and safety and pharmacokinetics were assessed. In the treatment phase, patients were treated with open-label galantamine according to regular clinical care. After 6 months of galantamine treatment, patients were categorized as either responder or as non-responder based on their MMSE, NPI and DAD scores. An analysis of covariance was performed to study the difference in acute PD effects during the challenge phase between responders and non-responders.

RESULTS

A single dose of galantamine significantly reduced saccadic reaction time (-0.0099; 95%CI=-0.0195,-0.0003; p=.0430), absolute frontal EEG parameters in alpha (-14.9; 95%CI=-21.0,-8.3; p=.0002), beta (-12.6; 95%CI=-19.4,-5.3; p=.0019) and theta (-17.9; 95%CI=-25.0,-10.0; p=.0001) frequencies. Relative frontal (-1.669; 95%CI=-2.999,-0.339; p=.0156) and occipital (-1.856; 95%CI=-3.339,-0.372; p=.0166) EEG power in theta frequency and relative occipital EEG power in the gamma frequency (1.316; 95%CI=0.158,2.475; p=.0273) also increased significantly compared to placebo. Acute decreases of absolute frontal alpha (-20.4; 95%CI=-31.6,-7.47; p=.0046), beta (-15.7; 95% CI=-28.3,-0.93; p=.0390) and theta (-25.9; 95%CI=-38.4,-10.9; p=.0024) EEG parameters and of relative frontal theta power (-3.27%; 95%CI=-5.96,-0.58; p=.0187) on EEG significantly distinguished responders (n=11) from non-responders (n=32) after 6 months.

CONCLUSIONS

This study demonstrates that acute PD effects after single dose of galantamine are correlated with long-term treatment effects and that patients who demonstrate a reduction in EEG power in the alpha and theta frequency after a single administration of galantamine 16 mg will most likely respond to treatment.

The Cambridge Neuropsychological Test Automated Battery (CANTAB) Versus the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) for the Assessment of Cognitive Function in Patients with Multiple Sclerosis

BACKGROUND

We determined how the Cambridge Neuropsychological Test Automated Battery (CANTAB) compared to the Minimal Assessment of Cognitive Function in multiple sclerosis (MACFIMS) in terms of sensitivity, specificity, and predictive values in detecting cognitive impairment in multiple sclerosis (MS) patients.

METHODS

Sixty MS patients were recruited, 2 of whom were lost to follow-up. On the first day of the neuropsychological examination, the standard MACFIMS battery and the day after, the CANTAB (paired-associate learning (PAL), reaction time (RTI), rapid visual information processing (RVP), and spatial working memory tasks (SWM)) were completed by the patients. The sensitivity, specificity, and predictive values of the CANTAB in the differentiation of cognitively impaired (CI) patients from not cognitively impaired (NCI) ones were compared with those of the MACFIMS battery using appropriate statistical tests.

RESULTS

Fifty-eight patients were categorized into two groups of CI (n=16 (27.58%)) and NCI (n=42 (72.41%)) based on the MACFIMS battery standard criteria. The best reporter indices and their cut-off scores for differentiation of CI from NCI patients in each task of the CANTAB were "total errors=13" for PAL, "between errors=26" for SWM, "five-choice reaction time=368.57" for RTI, and "mean latency=522.14" for RVP. The optimal cut-off point for distinguishing CI from NCI in the CANTAB was found to be an impaired function in 3 or more tasks [(AUC (95% CI): 0.97 (0.94-1.00); p<0.001)]. Accordingly, 36.20% of the patients were CI based on the CANTAB criteria. The inter-test agreement (CANTAB and MACFIMS batteries) was found to be the highest (Cohen's κ (95% CI): 0.80 (0.64-0.96)).

CONCLUSION

Results confirm that the CANTAB can discriminate CI from NCI MS patients with high accuracy, and its results are comparable to those of the MACFIMS battery; thus, they might be interchangeably used in the clinical practice.

Perception of Fechner Illusory Colors in Alzheimer Disease Patients

BACKGROUND Alzheimer disease (AD) primarily affects cognition. A variety of visual disorders was established in AD. Fechner illusory colors are produced by a rotating disk with a black and white pattern. The purpose of our research was to explore the perception of illusory colors in AD. MATERIAL AND METHODS W recruited 40 AD patients (MMSE ≥14) and 40 normal controls (CG group) matched by age, education, gender in this prospective, cross-sectional, case-control study. An achromatic Benham's disk attached to a device to control the speed and direction of rotation was used to produce illusory colors. Primary, secondary, and tertiary RGB system colors were used for matching of illusory and physical colors. RESULTS Subjects in the AD group perceived less illusory colors in 5 arcs (p<0.05) of the 8 arcs assessed. The biggest difference was found between AD and CG groups for pure blue (χ²=26.87, p<0.001 clockwise, χ²=22.75, p<0.001 counter-clockwise). Groups did not differ in perception of pure yellow opponent colors (p>0.05). Mixed colors of the blue-yellow axis were perceived less often in AD, but more frequently than pure blue (#0000FF). The sequence of colors on Benham's disk followed a complex pattern, different from the order of physical spectral colors and opponent processes-based colors. CONCLUSIONS AD patients retained reduced perception of illusory colors. The perception of pure blue illusory color is almost absent in AD. The asymmetrical shift to the yellow opponent is observed in AD with red prevailing over green constituent. This may indicate cortical rather than retinal impairment.

Specific Features of Executive Dysfunction in Alzheimer-Type Mild Dementia Based on Computerized Cambridge Neuropsychological Test Automated Battery (CANTAB) Test Results

BACKGROUND The primary manifestation of Alzheimer's disease (AD) is decline in memory. Dysexecutive symptoms have tremendous impact on functional activities and quality of life. Data regarding frontal-executive dysfunction in mild AD are controversial. The aim of this study was to assess the presence and specific features of executive dysfunction in mild AD based on Cambridge Neuropsychological Test Automated Battery (CANTAB) results. MATERIAL AND METHODS Fifty newly diagnosed, treatment-naïve, mild, late-onset AD patients (MMSE ≥20, AD group) and 25 control subjects (CG group) were recruited in this prospective, cross-sectional study. The CANTAB tests CRT, SOC, PAL, SWM were used for in-depth cognitive assessment. Comparisons were performed using the t test or Mann-Whitney U test, as appropriate. Correlations were evaluated by Pearson r or Spearman R. Statistical significance was set at p<0.05. RESULTS AD and CG groups did not differ according to age, education, gender, or depression. Few differences were found between groups in the SOC test for performance measures: Mean moves (minimum 3 moves): AD (Rank Sum=2227), CG (Rank Sum=623), p<0.001. However, all SOC test time measures differed significantly between groups: SOC Mean subsequent thinking time (4 moves): AD (Rank Sum=2406), CG (Rank Sum=444), p<0.001. Correlations were weak between executive function (SOC) and episodic/working memory (PAL, SWM) (R=0.01-0.38) or attention/psychomotor speed (CRT) (R=0.02-0.37). CONCLUSIONS Frontal-executive functions are impaired in mild AD patients. Executive dysfunction is highly prominent in time measures, but minimal in performance measures. Executive disorders do not correlate with a decline in episodic and working memory or psychomotor speed in mild AD.

The Effect of Chronic Alprazolam Intake on Memory, Attention, and Psychomotor Performance in Healthy Human Male Volunteers

Alprazolam is used as an anxiolytic drug for generalized anxiety disorder and it has been reported to produce sedation and anterograde amnesia. In the current study, we randomly divided 26 healthy male volunteers into two groups: one group taking alprazolam 0.5 mg and the other taking placebo daily for two weeks. We utilized the Cambridge Neuropsychological Test Automated Battery (CANTAB) software to assess the chronic effect of alprazolam. We selected Paired Associates Learning (PAL) and Delayed Matching to Sample (DMS) tests for memory, Rapid Visual Information Processing (RVP) for attention, and Choice Reaction Time (CRT) for psychomotor performance twice: before starting the treatment and after the completion of the treatment. We found statistically significant impairment of visual memory in one parameter of PAL and three parameters of DMS in alprazolam group. The PAL mean trial to success and total correct matching in 0-second delay, 4-second delay, and all delay situation of DMS were impaired in alprazolam group. RVP total hits after two weeks of alprazolam treatment were improved in alprazolam group. But such differences were not observed in placebo group. In our study, we found that chronic administration of alprazolam affects memory but attentive and psychomotor performance remained unaffected.